Skyrim:Ravage Health

Alchemy description:Causes <mag> points of concentrated poison damage.
This effect is a variant of Damage Health. It causes a flat total reduction of <mag> points of target's maximum Health points instantaneously.

As with the other two Damage Health variants, it is only available from potions.

The effects of Ravage Health can be reversed by altars and Potions of Cure Poison

The Ravage Health effect would be most effective when utilized against Trolls, since it decreases the Maximum Health. Trolls would therefore be unable to regenerate that lost health without potions, or curing at an altar; something they cannot do.

Additionally Ravage Health poisons would be a good choice against Mage opponents, since it would prevent them from healing with Restoration Magic and most don't carry Cure Poison.